This invention relates to road feature or asset mapping, and, more particularly to an apparatus for recording custom road feature or asset descriptions with accurate location information. The invention also encompasses a method for recording custom road feature descriptions with automatically captured feature location information.
All transportation and road maintenance agencies maintain road or highway inventory records which they must update periodically. Most of these records are created by tagging or identifying each feature or asset along the particular road with an elapsed distance from a reference point. These "logmile" tags are almost universally used for recording the location of assets and features along a road or highway.
A number of different methods have been developed for recording road feature or asset inventory data. The simplest data collection method comprises travelling along the particular road and manually writing out or dictating each feature being inventoried with a corresponding logmile value observed from a vehicle's trip odometer. Automated data entry systems have also been developed in which a device operator uses a keyboard or a touch-sensitive screen to automatically record a pre-defined or canned feature description and simultaneously capture a logmile for the particular feature description. In some cases the prior information recording methods substituted a global positioning system navigation receiver for the distance measuring instrument or odometer so as to provide absolute feature or asset location information in terms of latitude, longitude, and altitude. In these road feature or asset recording systems, a global positioning system (GPS) time mark was automatically captured when a standardized feature or asset description was entered through a keyboard or a touch-sensitive screen.
Another prior method of recording road feature or asset information employed a voice speech recognition system to enter standardized feature descriptions. The voice speech recognition system replaced the keyboard or touch-sensitive screen input and was "pre-trained" to recognize an individual operator's pronunciation of certain feature cues. The system then automatically recorded the particular standardized feature description corresponding to each cue spoken by the operator. Even though the feature description recording sequence in these systems was started by a voice signal, the feature descriptions that were recorded were merely standardized descriptions like the keyboard and touch screen entry systems.
There were a number of problems associated with the prior road inventory data collection techniques. The simple written or dictated feature description and odometer reading technique was flexible and allowed customized feature descriptions, but was time consuming and required two operators to safely record all of the required information and also drive the vehicle along the road. These prior inventory data collection techniques required one operator to drive the vehicle and another operator to poll odometer readings and dictate or otherwise record the asset or feature descriptions.
On the other hand, the standardized feature description techniques, in which standardized feature descriptions were entered through keyboards, touch-sensitive screens, or voice recognition systems, in some cases required only one operator but were inflexible with regard to the feature descriptions that could be recorded. In many cases a feature or asset required some custom description that was not available in the menu of standardized feature or asset descriptions. Standardized feature description techniques have therefore been limited to special purpose applications.
There has therefore been a need for an inventory data collection technique that has the flexibility of the two person custom feature description techniques and yet can be operated by a single operator while the operator drives the vehicle along the road which is to be inventoried.